Cleaning stain out of pump sprayer

What methods and products do you use to clean out the stain from your pump sprayer (or deckster or whatever you use)

Depends on what type of stain, oil based, latex? I either use paint thinner or warm soap & water. As soon as I’m done with it I run water through it so nothing gets clogged. When I get back to the shop I give it a good once over.